This application claims the priority of Document No. 100 51 668.8, filed in Germany on Oct. 18, 2000, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a folding rear seat for vehicles, especially passenger vehicles and station wagons. Preferred embodiments of the invention relate to a seat back that can pivot about a pivotal axis extending perpendicular to a longitudinal axis of a vehicle, and a height-adjustable neck support mounted on the seat back on at least one support rod that is held such that it can shift axially within a guide mechanism in the seat back; said neck support supporting a padded head rest which can be retracted from a temporary vertical position to a minimum possible distance between the padded head rest and the seat back to allow the seat back to be folded.
Folding rear seats in passenger vehicles and station wagons serve to create additional cargo space in the area behind the two front seats, wherein the rear surface of the seat back, which is folded down onto the seat or seat cushion of the rear seat, can be used as a storage surface; or wherein the whole package composed of the seat and the folded down seat back is folded up against the rear surface of the back of the front seat, allowing the space that is opened up by the rear seat to be used as additional cargo space. Due to the limited space available in a vehicle, in order for the seat backs to be folded down completely onto the seats, the neck supports must be removed from the seat backs or at least moved from their temporary vertical adjustment position to their lowest possible position, to prevent interference with the folding down of the seat back.
In one known rear seat of this type (German Patent Document DE 33 06 188 C2), a recessed, padded area is provided in the upholstery of the seat back, and the neck support and the padded area are coordinated kinematically with one another such that when the seat back is folded down against the force of a readjusting spring, the padded section is moved in front of the seat back, at a distance from its upper edge, and the padding of the neck support becomes engaged in the recessed area that is opened up. When the seat is folded back up, the readjusting spring serves to ensure that the neck support, and thus necessarily the padded head rest, returns to its original position. In order to achieve these kinematics, the two rods that support the padded head rest are held within sleeves, which are fastened within a carriage that is mounted in the guide mechanism. The support rods for the neck support are oriented within the sleeves such that they can shift axially, and the neck support is locked in at each vertical position through catch devices in the sleeve. The readjusting spring is positioned between the carriage and the seat back, and a cable that gets shorter when the seat back is folded down is engaged in the carriage. In order to direct the padded head rest into the recess created by the padded component when the seat is being folded down, the head rest must first be moved from its temporary vertical position to its lowest possible position, the so-called minimum possible distance, by pressing down on catch devices between the support rods and the sleeves, and pushing the padded head rest down by hand until its lower edge rests against the upper edge of the seat back. The vertical position the padded head rest was in before the seat was folded down must then be reset manually by pulling the neck support from its minimum position while pressing down on the catch devices.
The prescribed legal safety standards for passenger vehicles provide that when the rear seat is being used, the padded head rest may not go below a certain vertical adjustment position, which represents a minimum limit for use of the neck support. This minimum point for the vertical position of the padded head rest is 750 mm, measured from the so-called SAP. However, when the seat back is folded down, due to limited spatial relationships, especially in vehicles in the compact class, the neck support must necessarily fall below this minimum limit.
An object of the invention is to ensure, with a seat back of the type described at the beginning and through technically simple means, that after the seat back has been returned to its original position for use as a seat, the padded head rest, which was pushed down below the allowable limit when the seat back was folded down, will automatically return to its prescribed minimum vertical position.
The object is attained in accordance with preferred embodiments of the invention by providing a rear seat comprising a seat back that can pivot about a pivotal axis extending perpendicular to a longitudinal axis of a vehicle, and a height-adjustable neck support mounted on the seat back on at least one support rod that is held such that it can shift axially within a guide mechanism in the seat back. The neck support supports a padded head rest which can be retracted from a temporary vertical position to a minimum possible distance between the padded head rest and the seat back to allow the seat back to be folded. The guide mechanism is formed by at least one guide sleeve that holds the support rod such that it can shift axially. A spring element is positioned between the guide sleeve and the support rod such that the spring element is first tensed by the support rod when the height of the neck support is reduced by force of pressure from a prescribed vertical position for the padded head rest to a predetermined minimum distance. The spring element is operable to push the support rod back to the prescribed vertical position for the padded head rest when the force of pressure has been removed.
The folding rear seat specified in the invention offers the advantage that, without a constructive redesigning of the neck support or the mounts for the neck support in the seat back, but rather merely by incorporating a simple, spring element, the neck support can be pushed into the seat back the small amount that is required to permit the seat back to be folded down, while ensuring that when the seat back is folded back up for use as a seat, the padded head rest will automatically return to its legally prescribed, preset minimum vertical position, without any help from the user. The neck support is pushed down from the legally prescribed vertical position for the padded head rest in that when the padded head rest reaches the rear surface of the seat back of the front seat, the seat back is swiveled further, causing the padded head rest, under tension from the spring element and the support rods, to follow the contours of the rear surface of the back of the front seat. If the axis of rotation for the seat back is in the seat cushion of the rear seat, and the seat cushion itself can also be folded up on an axis of rotation located at the front of the seat cushion, then, when the seat cushion, with its seat back folded down on top of it, is folded up against the rear surface of the seat back of the front seat, the force of pressure acting on the padded head rest is provided by the floor space against which the padded head rest is turned when the seat cushion is folded up. By utilizing the components in the vehicle""s interior that lie along the folding pathway for the seat back, namely the front seat back and the floor, the neck support, pressed against the spring element, does not need to be locked into position, hence no means for unlocking the neck support are necessary. This also serves to keep manufacturing costs down.
Advantageous embodiments of the rear seat specified in the invention, with further developments and designs for the invention, described below and in the claims.
In accordance with one preferred embodiment of the invention, the spring element is designed as a compression spring, one end of which rests against the base of the guide sleeve, while the other end rests against a spring plate that is designed to shift axially within the guide sleeve. The spring plate operates in conjunction with a stop motion device that serves to limit the maximum block length of the compression spring, and is mounted in the guide sleeve such that the spring plate rests against the end of the support rod when the padded head rest is in its prescribed vertical position. Preferably, the spring plate is also held on a threaded bolt that extends into the sleeve through its base, and the stop motion device is formed by the bolt head or by a counter nut that is screwed onto the end of the bolt. To adjust the neck support to a vertical position that is comfortable for the individual user, the padded neck support must be moved manually, as is known in the art, out of its prescribed vertical position by pressing down on the catch device between at least one guide sleeve and at least one support rod.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the present invention when considered in conjunction with the accompanying drawing.